The present invention relates to a variable configuration automobile vehicle seat.
There is already known in the art, in particular from FR-A-2 556 294, a variable configuration automobile vehicle seat of the type comprising:
a base assembly adapted to be fixed to the body of the vehicle,
an articulated support assembly comprising front and rear support links for a seat cushion of the seat each of which has two ends articulated about axes respectively fixed relative to the seat cushion and to the base assembly,
means for adjusting the angular position of the support links relative to the seat cushion, and
means for controlling the position of a seat back of the seat relative to the seat cushion.
A seat of the above type enables the seat cushion and the seat back to be moved simultaneously to change the seat from a normal configuration to a relaxation configuration in which, compared to the normal configuration, the top of the seat back is inclined rearwardly and the front of the seat cushion is moved and raised forwardly.
The articulated support system of the seat described in FR-A-2 556 294 is operated by two actuators and is relatively complex. Moreover, because they can operate on either actuator, there is a risk that occupants of the seat may unintentionally move the seat into a hazardous configuration such that the position of the seat cushion relative to the seat back encourages xe2x80x9csubmariningxe2x80x9d of the occupant. Submarining causes the occupant of the seat to slip under the abdominal strap of the seat belt usually associated with the seat.
The object of the invention is to propose a seat of the aforementioned type, which is easy to manoeuvre, reliable and strong and very safe.
To this end, the invention provides a variable configuration automobile vehicle seat of the aforementioned type which is characterised in that the control means comprise an articulated quadrilateral which has four corners, a first corner is connected to the seat cushion and the second and fourth corners are connected to the seat back.
According to other features of the seat:
the first corner of the control quadrilateral coincides with the articulation axis of the rear support link, which is fixed relative to the seat cushion,
the articulated control quadrilateral is convex, the second corner is connected to the seat cushion and to the base assembly, and the articulated quadrilateral is materialised by the support link which defines the first and second corners of the quadrilateral and by a control link which defines the third and fourth corners of the quadrilateral and which has two ends articulated about axes respectively fixed relative to the seat cushion and to the seat back,
it has releasable means for locking the seat back to the fourth corner of the articulated quadrilateral so that after the locking means are released the seat back can pivot about the second corner of the quadrilateral between an upright normal position of use and a position folded against the seat cushion,
the locking means comprise a pin materialising the fourth corner of the articulated quadrilateral and a hook articulated to the seat back and adapted to cooperate with the pin and the second and fourth corners are connected together by a connecting link,
the articulated control quadrilateral is concave, the second corner is connected to the seat cushion and to the seat back and coincides with an articulation axis of the seat back which is fixed relative the seat cushion, the articulated quadrilateral is materialised by the seat cushion extending between the first and second corners of the quadrilateral and by a control link which defines the third and fourth corners of the quadrilateral and which has two ends articulated about axes fixed relative to the seat back and to the rear support link, and the axis about which the control link is articulated to the rear support link is placed on the rear support link between the axes about which the rear support link is articulated to the seat cushion and to the base assembly,
the means for adjusting the angular position of the support links relative to the seat cushion comprise an actuator having two ends articulated about axes respectively fixed relative to the seat cushion and to one of the support links,
the actuator is of a mechanical type, for example of the screw and nut type,
the ends of the actuator are articulated to the front of the seat cushion and to the front support link and the axis about which the actuator is articulated to the front support link is placed on the front support link between the axes about which it is articulated to the seat cushion and to the base assembly,
the ends of the actuator are articulated to the rear of the seat cushion and to the rear support link and the axis about which the actuator is articulated to the rear support link is placed on the rear support link between the axes about which it is articulated to the seat cushion and to the base assembly, and
the base assembly comprises a front rail connected to the front support link and a rear rail connected to the rear support link.